The present invention relates to containers for viscous and other fluids and to improvements in the containment, dispensing and handling of the fluids; being more particularly, though not exclusively, concerned with architectural coatings such as paints and the like and to significant improvement in current paint can design.
Nearly all one-gallon and smaller containers of paint are sold in cylindrical metal cans having an upper edge with a groove that accepts the annular protrusion of a high friction metal lid secured by a press fit. This arrangement has many operational drawbacks that the industry has put up with for many decades. These include the lack of a locking mechanism that would prevent the friction lid, popping off if the can is dropped from a height as little as one meter, with consequent spilling of the contents widely on the ground. The lid, moreover, must be pried off with a tool to gain access to the paint, which proves a problem if no tool is available. The prying action, moreover, often damages the lid sealing surface. The can lip, furthermore, makes a very poor spout. When the paint contents are transferred to another container, they must be poured across the grooved upper edge of the can, which inherently retains some of the paint, and the paint running down the outside of the can often obscure the label, potentially reaching the users hands and the bottom surface. The can, indeed, must be wiped nearly every time it is poured. With the inside of the upper rim trapping paint as it is poured, the user is never able to extract all available paint even if a brush is used. The circular shape of the can opening, in addition, is ineffective for wiping a flat brush clean of excess paint. Every time paint is poured from a can, the groove that accepts the lid fills with paint and it is very difficult to clean completely. After repeated opening, pouring, and closing, in addition, the mating surface becomes fouled and the friction seal fails.
Perhaps the biggest drawback of the current paint can, however, resides in the splattering of paint from the groove as the lid is pounded back on. The pounding of the lid often damages both sealing surfaces, which again can cause the seal to fail. Furthermore, paint in and around the groove can dry out and flake, leading to paint contamination each time the can is jostled. While metal cans are coated to prevent rust, this coating often fails, which leads to rust and paint contamination. Paint cans, in addition, do not stack well, and little disturbance is needed to cause them to slide off of one another.
Many efforts have been made to address these and other problems associated with the conventional metal paint can. Some prior are improvements remedy to some degree some of the shortcomings mentioned above, but none, until the present invention, has effectively solved even a majority of these problems.
As an example, U.S. Pat. No. 5,669,526 discloses a plastic paint can that has a small-diameter, collapsible spout, non-contaminating lid seal, and straight edge formed in the can opening to facilitate brush wiping. This configuration, however, only addresses problems of paint contamination, messy pouring, and non-uniform brush wiping inherent in the conventional metal paint can. The narrow spout opening causes a slow pour rate and an undesirable chugging action as contents are poured.
U.S. Pat. No. 5,269,438 discloses a container with features designed to improve dispensing, such as a pivotally mounted carrying handle that is offset from the opening to provide access. It also has a wide pouring channel to improve flow, addressing to some degree a number of deficiencies. The pop top of the lid, however, is not very secure and the spout does not prevent paint running down the side of the container.
A plastic container having a threaded lid that closes the container either by screw-down or snap-on action is proposed in U.S. Pat. No. 4,453,647. A depression is formed in the lid to accept a mixing stick or the like to aid in tightening and undoing the lid. This configuration, however, only addresses the problems of paint contamination and the difficult opening and closing of the lid inherent in the conventional metal paint can. As the contents are poured, they can still coat container threads and run down the side of the container. A tool, in particular a paint mixing stick, not always available, is required, moreover, to open the lid.
In U.S. Pat. No. 4,917,268, there is disclosed a liquid-dispersing package with a spout that has a drain back channel to return liquid drips to the container. This configuration, however, only addresses the problem of difficult, messy pouring inherent in containers intended for dispensing low viscosity liquids, but it does not work will with moderate viscosity fluids, such as paint. The tall and narrow design, moreover, eliminates the stackability of the container.
U.S. Pat. No. 5,054,661, as another illustration of attempts to improve the pouring operation, discloses a pouring spout that extends outwardly of the upper edge of the container, and an opposing handle projected from the upper edge of the container. It is also primarily intended to facilitate dispensing of paint during painting. In this invention, however, there is also no means to store the paint, and any unintended spillage during pouring will also wet exterior surfaces.
U.S. Pat. No. 4,619,373 discloses a plastic paint container with a lid that seals within the inner diameter of the rim at the top of the container, to eliminate the poor sealing characteristics of the friction lid of the metal paint can. It is still subject, however, to contamination of the seal by the paint itself, and does not provide for clean use or dispensing.
Another proposal, in U.S. Pat. No. 4,245,753 also provides a plastic paint container, but with a snap-on, screw-off type of lid. It also provides a stacking construction and a hollow handle. The design addresses the sealing and opening/closing problem with the metal paint can friction lid, and aids in stacking containers together. Like the other prior art, however, it does not provide for clean dispensing or use, nor does it address the difficulty that would be encountered with hand rotation of a firmly engaged, large diameter friction seal lid.
Numerous other prior art proposals provide for attaching auxiliary components to existing metal cans. Attachments are inherently deficient because they all require the additional operations of the attachment, removal, and cleaning which are inconvenient to the user. For example, U.S. Pat. No. 4,702,395 discloses a handle and pouring-spout arrangement intended for attachment to a conventional metal paint can. The spout has an optional paint-drainback section. This configuration, moreover, only attempts to solve the problem of difficult, messy pouring from conventional metal paint cans.
In U.S. Pat. No. 4,949,884, as another illustration, a removable top to a conventional metal can is proposed to attempt to solve these problems of difficult, messy pouring from conventional paint cans. Again, it must be attached and removed not only for every opening and closing, respectively, but also every time a brush is to be used.
While the above-mentioned advances in the art each solve to some degree some of the major problems inherent in the conventional metal paint can, none of them solves a majority of the problems. Some, moreover, improve only a subset of the problems and make improvements at the expense of some current favorable can features. The present invention, on the other hand, synergistically solves nearly all of the major problems above-enumerated inherent in the conventional metal paint can.